Racial tension isn't what it used to be. The more sensitive we become, the more ways we have of stepping on each other's toes, and the harder we try to say and do the right thing, the more frustration builds up inside us until we're all walking powder kegs.

As Lawrence Kasdan's Grand Canyon reported on the state of race relations in Southern California in 1991, Crash brings us up to date for 2005. Some of the old problems have moved to the back burner as more racial groups have reached critical mass and our ignorance and fear appear to have grown apace.

I don't care if you're the love child of Martin Luther King Jr. and Mother Teresa, you've got some racism inside you, and Crash will find it. Be prepared to squirm.

Situations range from overt acts of hatred and angry outbursts to the way tension escalates in simple encounters (e.g., fender-benders, frustration with insurance company bureaucracy) when the parties involved are of different races.

A Persian shopkeeper (Shaun Toub) buys a gun from a dealer who calls him an Arab (and therefore a terrorist) and will only sell the gun to the man's more Americanized daughter.

Police Detective Don Cheadle investigates the killing of a black cop by a white cop. There are questions– Who shot first? Was the black cop dirty? Was the white cop racist?– but what really matters is putting the most politically advantageous spin on the case.

Los Angeles District Attorney Brendan Fraser is also concerned about political repercussions when he and his wife (Sandra Bullock) are carjacked by black thugs Chris "Ludacris" Bridges and Larenz Tate. Bullock, however, is free to take it out on everyone from the Mexican (Michael Peña) who changes their locks to their Latina maid (Yomi Perry).

TV producer Terrence Howard and his wife (Thandie Newton) are hassled and humiliated by white cop Matt Dillon while his partner (Ryan Phillippe) stands helplessly by. Howard is used to walking on eggshells around whites (including Tony Danza) at work.

Ludacris, who amusingly gets to state the case against hip-hop, is proud of never having robbed anyone of his own race: "The only reason black people steal from their own is that they're terrified of white people."

Each situation is fraught with disastrous possibilities, and several build to the point where the worst-case scenario seems inevitable. Some tragedies are averted, some aren't; but the ones that are are averted in miraculous ways that leave you with hope.

With his first feature as director, Paul Haggis, who adapted the screenplay of Million Dollar Baby, shows himself equally skilled in both fields of endeavor. As the stories develop and interweave, there's one coincidence (out of dozens) that's too much for me to accept, but it sets up arguably the film's most powerful scene.

Most of Crash takes place on Christmas Eve. No one mentions the holiday, but the decorations are everywhere. It can't be coincidental that snow falls before it's over, giving L.A. a rare white Christmas. At least it doesn't rain frogs.

Haggis says the story was inspired by an incident in 1991 when he and his wife were carjacked by two young black men. It will be the ultimate irony if those men now come forward and sue for a share of the profits. But that could only happen in the movies.